Although every U.S. president since Herbert Hoover has stayed at the famous luxury Waldorf Astoria Hotel when visiting New York City, President Obama will not be bunking there this week. Along with hundreds of American officials who used to occupy whole floors of the Waldorf during the September meetings of the U.N. General Assembly, Obama will move to a different hotel.

No explanation has been announced, but the obvious reason is that U.S. officials wouldn't be safe or secure there. The Waldorf was bought last year by a Chinese insurance company whose directors are connected to the Chinese Communist Party and the People's Liberation Army, and so we assume the commies could listen to private conversations between Obama and other VIPs.

Last week Obama royally entertained China's so-called president, Xi Jinping, with a 21-gun salute on the White House lawn followed by a formal state dinner featuring the CEOs of two dozen leading corporations eager to do business with Communist China's state-owned enterprises.

The Communist Chinese have been waging cyber warfare against America for years. Our Office of Personnel Management admits the theft of personal information about more than 20 million Americans, including fingerprints, financial history and other sensitive data, and the U.S. has done nothing about these offenses.

Our top reporter of Chinese mischief, Bill Gertz, reports that China has redirected 20 to 30 percent more funding to cyber warfare, which they consider a primary tool in their drive to achieve world domination and to control world trade. This cyber warfare capacity has enabled the Chinese to steal hundreds of billions of dollars worth of intellectual property from U.S. businesses.

All of China's theft of our business and computer secrets, however, is not carried out by exotic technology. Some of it is by old-fashioned espionage, which has been facilitated by the fact that China has passed Mexico as the top source of new U.S. immigrants.

The number of Chinese students in U.S. universities has risen 75 percent over the past three years to nearly 275,000 -- more than any other country. University administrators love the foreigners because they are cash customers paying the full tuition price.

Some come through the racket called "birth tourism." That's the scheme in which a pregnant woman pays someone to house her in California until she gives birth and gets a U.S. birth certificate for her baby, which guarantees all sorts of government-paid goodies.

U.S. authorities just brought criminal charges against three New York University research professors for conspiring to take bribes from Chinese medical and research outfits for turning over details about NYU research into magnetic resonance imaging (MRI) technology. The FBI said the three professors conspired to be paid by a Chinese medical imaging company controlled by the Chinese government.

The mantra "free trade," so glibly and repeatedly echoed by businessmen and politicians, is a joke in China; China has become increasingly and profoundly protectionist, which means China protects its own industries at the expense of every other country.

China passed a national security law mandating that all information systems operating in China be "secure and controllable," and that all businesses operating in China, both Chinese and American, must sign this pledge. It isn't quite clear what that phrase means, but Americans believe it means providing backdoors in software to allow government monitoring.

When U.S. firms seek to enter China and build manufacturing plants there, China requires them to share their intellectual property and manufacturing know-how with Chinese state-owned enterprises, thereby enabling China to eventually design and build its own plants to take the business away from U.S. companies. That's a clear violation of the rules of the World Trade Organization, but we do nothing to stop it.

In the latest example, U.S. tech giant Cisco, which builds America's most advanced computer routers, has just agreed to invest $10 billion in partnership with a Chinese state-owned server company. "There are certain geopolitical dynamics that we have to navigate," Cisco's CEO sheepishly admitted -- in other words, the practice of transferring technology is part of doing business in China.

Meanwhile, China is starting to show off its new military power. Two Chinese jet fighters buzzed a U.S. plane within only 500 feet in the sky just days before China's president was set to be received by Obama at the White House. Our military officials called this another "unsafe intercept," after a similarly dangerous maneuver by a Chinese pilot in August of last year.

Five Chinese Navy ships were seen prowling the Bering Sea off the coast of Alaska during Obama's three-day tour of that state. Four thousand miles away, China is building and fortifying several islands in the South China Sea to serve as its "unsinkable aircraft carriers."